This invention relates to improved methods and apparatus for filling an insulating material into a cavity or cavities within the interior of a building panel.
The panels with which the invention is concerned are of a known type which may be pre-fabricated before delivery to a building site, and then assembled and secured together in side by side relation at the site so that a series of interconnected panels of this type can form together a wall or walls of a building. Each panel may include the studs in appropriate spacing for a particular part of the overall building wall structure, with both inside and outside skins or walls applied to the studs at their opposite sides and typically formed of plywood at the outer side of the building and sheet rock at its inner side. In some instances in the past, a foaming type resinous plastic insulating material has been injected into the cavities within the interior of panels of this type to produce a cellular mass occupying such cavities and containing a large number of air spaces acting to give the overall panel a very effective heat insulating characteristic. One difficulty which has been encountered in the past in producing such insulated building panels has resulted from the tendency for the side walls or skins of the panel and the intermediate studs and other components of the overall panel to distort or shift slightly under the forces which may be exerted by the insulating material as it is injected into the cavities within the interior of the panel and then cured therein.